In 1955, Michael Vierkant, a Jew who had emigrated during the Nazi era, returns from abroad to the Federal Republic of Germany to obtain the conviction of Korn, the former informer responsible for the murder of his sister. Korn is back in office; Michael's efforts remain unsuccessful. There is a direct confrontation between the two, and Michael shoots Korn in self-defense. He flees and is hidden by the young, reclusive artist Marie Jäger, but is then caught by the police and charged with premeditated murder. The case is taken out of the hands of the criminal investigation department by the Office for the Protection of the Constitution, which constructs an act of political revenge on behalf of the communists. Michael manages to escape from prison. Marie and her friends organize a press conference at which Michael reveals the connections. The trial is postponed.